Sonodynamic therapy (SDT) triggered by ultrasound (US) has attracted increasing attention owing to its abilities to overcome critical limitations including low tissue‐penetration depth and ...phototoxicity in photodynamic therapy. Herein, the design of a new type of sonosensitizer is revealed, namely, ultrasmall oxygen‐deficient bimetallic oxide MnWOX nanoparticles, for multimodal imaging‐guided enhanced SDT against cancer. As‐made MnWOX nanoparticles with poly(ethylene glycol) (PEG) modification show high physiological stability and biocompatibility. Interestingly, such MnWOX‐PEG nanoparticles exhibit highly efficient US‐triggered production of 1O2 and •OH, higher than that of previously reported sonosensitizers (e.g., protoporphyrin IX and titanium dioxide), because the oxygen‐deficient structure of MnWOX serves as an electron trap site to prevent electron–hole recombination. The glutathione depletion capability of MnWOX‐PEG can also further favor SDT‐triggered cancer cell killing. With efficient tumor homing as illustrated by computer tomography and magnetic resonance imaging, MnWOX‐PEG enables effective destruction of mouse tumors under US stimulation. After accomplishing its therapeutic functions, MnWOX‐PEG can be metabolized by the mouse body without any long‐term toxicity. Herein, a new type of sono‐sensitizing agent with high SDT efficacy, multimodal imaging functions, and rapid clearance is presented, an agent which is promising for noninvasive SDT cancer treatment.
A new type of sonodynamic therapy (SDT) agent based on ultrasmall oxygen‐deficient bimetallic oxide MnWOX nanoparticles, which exhibit much higher sono‐sensitization efficiency compared with conventional SDT agents, as well as glutathione depletion capability to further favor SDT. Furthermore, their multimodal imaging functions and rapid renal clearance make them promising theranostic agents for imaging‐guided SDT.
Paclitaxel (PTX) can bind to human serum albumin (HSA) via hydrophobic interaction, forming Abraxane, which is a U.S. Food and Drug Administration (FDA) approved effective antitumor nanomedicine ...drug. Herein, the effective antitumor drug PTX is used to induce the self-assembly of HSA modified with either a photosensitizer chlorin e6 (Ce6), which at the same time serves as a chelating agent for Mn2+ to enable magnetic resonance imaging, or acyclic Arg-Gly-Asp (cRGDyK) peptide that targets αvβ3-integrin overexpressed on tumor angiogenic endothelium. Two types of tumor-targeting theranostic nanoparticles are constructed, either by coassembly of both HSA-Ce6 and HSA-RGD simultaneously or by forming an HSA-Ce6@HSA-RGD core–shell structure, with the assistance of PTX-induced albumin aggregation. Such albumin-based nanoparticles on one hand could targetαvβ3-integrin, as evidenced by both in vitro and in vivo experiments, and on the other hand enable combined photodynamic/chemotherapy, which offers remarkably improved therapeutic efficacy to kill cancer in comparison to the respective monotherapies. Our work presents a new type of tumor-targeted multifunctional albumin-based nanoparticles by drug-induced self-assembly, which is a rather simple method without any sophisticated chemistry or materials engineering and is promising for multimodel imaging-guided combination therapy of cancer.
Because excitation winding short-circuit faults that occur in steam-turbine generator will lead to heavy financial losses, accurately detecting excitation winding short-circuits (EWS) can help power ...generation operations. It can allow them to take timely actions and shorten downtime as well as cut the costs of troubleshooting. This paper introduces a method for detecting EWS faults online using a new detection coil. Here, a large-dimension detection coil is installed inside the generator to span over an iron-core segment in the stator. The even or fractional harmonics induced by the detection coil are used to determine whether an EWS fault has happened, and the short circuit position can also be determined. This method can reveal short-circuit faults that occur in one turn of the excitation winding, and with obviously higher sensitivity.
The development of cancer combination therapies, many of which rely on nanoscale theranostic agents, has received increasing attention in recent years. In this work, polyethylene glycol (PEG) ...modified mesoporous silica (MS) coated single‐walled carbon nanotubes (SWNTs) are fabricated and utilized as a multifunctional platform for imaging guided combination therapy of cancer. A model chemotherapy drug, doxorubicin (DOX), could be loaded into the mesoporous structure of the obtained SWNT@MS‐PEG nano‐carriers with high efficiency. Upon stimulation under near‐infrared (NIR) light, photothermally triggered drug release from DOX loaded SWNT@MS‐PEG is observed inside cells, resulting in a synergistic cancer cell killing effect. As revealed by both photoacoustic (PA) and magnetic resonance (MR) imaging, we further uncover efficient tumor accumulation of SWNT@MS‐PEG/DOX after intravenous injection into mice. In vivo combination therapy using this agent is further demonstrated in a mouse tumor model, achieving a remarkable synergistic anti‐tumor effect superior to that obtained by mono‐therapy. Our work presents a new type of theranostic nano‐platform, which could load therapeutic molecules with high efficiency, be responsive to external NIR stimulation, and at the same time serve as a diagnostic imaging agent.
Mesoporous silica coated single‐wall carbon nanotubes with polyethylene glycol functionalization and anti‐cancer drug loading are developed as a multifunctional theranostic platform. Upon systemic administration of such nano‐agent, combined photothermal and chemotherapy, which is under the guidance of multimodal magnetic resonance and photoacoustic imaging, is conducted on an animal tumor model, achieving a great synergistic therapeutic effect.
Enhanced near-field at noble metal nanoparticle surfaces due to localized surface plasmon resonance (LSPR) has been researched in fields ranging from biomedical to photoelectrical applications. ...However, it is rarely explored on nonmetallic nanomaterials discovered in recent years, which can also support LSPR by doping-induced free charge carriers, let alone the investigation of an intricate system involving both. Here we construct a dual plasmonic hybrid nanosystem Au–Cu9S5 with well controlled interfaces to study the coupling effect of LSPR originating from the collective electron and hole oscillations. Cu9S5 LSPR is enhanced by 50% in the presence of Au, and the simulation results confirm the coupling effect and the enhanced local field as well as the optical power absorption on Cu9S5 surface. This enhanced optical absorption cross section, high photothermal transduction efficiency (37%), large light penetration depth at 1064 nm, excellent X-ray attenuation ability, and low cytotoxicity enable Au–Cu9S5 hybrids for robust photothermal therapy in the second near-infrared (NIR) window with low nanomaterial dose and laser flux, making them potential theranostic nanomaterials with X-ray CT imaging capability. This study will benefit future design and optimization of photoabsorbers and photothermal nanoheaters utilizing surface plasmon resonance enhancement phenomena for a broad range of applications.
Abstract A large variety of cancers are associated with a high incidence of lymph node metastasis, which leads to a high risk of cancer death. Herein, we demonstrate that multimodal imaging guided ...photothermal therapy can inhibit tumor metastasis after surgery by burning the sentinel lymph nodes (SLNs) with metastatic tumor cells. A near-infrared dye, IR825, is absorbed onto human serum albumin (HSA), which is covalently linked with diethylenetriamine pentaacetic acid (DTPA) molecules to chelate gadolinium. The formed HSA-Gd-IR825 nanocomplex exhibits strong fluorescence together with high near-infrared (NIR) absorbance, and in the mean time could serve as a T1 contrast agent in magnetic resonance (MR) imaging. In vivo bi-modal fluorescence and MR imaging uncovers that HSA-Gd-IR825 after being injected into the primary tumor would quickly migrate into tumor-associated SLNs through lymphatic circulation. Utilizing the strong NIR absorbance of HSA-Gd-IR825, SLNs with metastatic cancer cells can be effectively ablated under exposure to a NIR laser. Such treatment when combined with surgery to remove the primary tumor offers remarkable therapeutic outcomes in greatly inhibiting further metastatic spread of cancer cells and prolonging animal survival. Our work presents an albumin-based theranostic nano-probe with functions of multimodal imaging and photothermal therapy, together with a ‘photothermal ablation assisted surgery’ strategy, promising for future clinical cancer treatment.
Recently, near‐infrared (NIR) absorbing conjugated polymeric nanoparticles have received significant attention in photothermal therapy of cancer. Herein, polypyrrole (PPy), a NIR‐absorbing conjugate ...polymer, is used to coat ultra‐small iron oxide nanoparticles (IONPs), obtaining multifunctional IONP@PPy nanocomposite which is further modified by the biocompatible polyethylene glycol (PEG) through a layer‐by‐layer method to acquire high stability in physiological solutions. Utilizing the optical and magnetic properties of the yielded IONP@PPy‐PEG nanoparticles, in vivo magnetic resonance (MR) and photoacoustic imaging of tumor‐bearing mice are conducted, revealing strong tumor uptake of those nanoparticles after intravenous injection. In vivo photothermal therapy is then designed and carried out, achieving excellent tumor ablation therapeutic effect in mice experiments. These results promise the use of multifunctional NIR‐absorbing organic‐inorganic hybrid nanomaterials, such as IONP@PPy‐PEG presented here, for potential applications in cancer theranostics.
A novel type of multifunctional theranostic nanoparticles is developed by encapsulating ultra‐small iron oxide nanoparticles (IONPs) with polypyrrole (PPy), on top of which polyethylene glycol (PEG) is coated. The obtained IONP@PPy‐PEG nanoparticles with strong superparamagnetism and high near‐infrared absorbance enable in vivo dual‐modal magnetic resonance and photoacoustic imaging‐guided photothermal therapy, achieving excellent cancer ablation effect in animal experiments.
The occurrence of 14 antibiotics (fluoroquinolones, tetracyclines, macrolides and sulfonamides) in groundwater and surface water at Jianghan Plain was investigated during three seasons. The total ...concentrations of target compounds in the water samples were higher in spring than those in summer and winter. Erythromycin was the predominant antibiotic in surface water samples with an average value of 1.60μg/L, 0.772μg/L and 0.546μg/L respectively in spring, summer and winter. In groundwater samples, fluoroquinolones and tetracyclines accounted for the dominant proportion of total antibiotic residues. The vertical distributions of total antibiotics in groundwater samples from three different depths boreholes (10m, 25m, and 50m) exhibited irregular fluctuations. Consistently decreasing of antibiotic residues with increasing of depth was observed in four (G01, G02, G03 and G05) groundwater sampling sites over three seasons. However, at the sampling sites G07 and G08, the pronounced high concentrations of total antibiotic residues were detected in water samples from 50m deep boreholes instead of those at upper aquifer in winter sampling campaign, with the total concentrations of 0.201μg/L and 0.100μg/L respectively. The environmental risks posed by the 14 antibiotics were assessed by using the methods of risk quotient and mixture risk quotient for algae, daphnids and fish in surface water and groundwater. The results suggested that algae might be the aquatic organism most sensitive to the antibiotics, with the highest risk levels posed by erythromycin in surface water and by ciprofloxacin in groundwater among the 14 antibiotics. In addition, the comparison between detected antibiotics in groundwater samples and the reported effective concentrations of antibiotics on denitrification by denitrifying bacteria, indicating this biogeochemical process driven by microorganisms won’t be inhibitory influenced by the antibiotic residues in groundwater.
•Fourteen antibiotics were investigated in aquatic environment over three seasons.•Total concentrations of antibiotics in two water matrixes were highest in spring.•The vertical variations of antibiotic residues in groundwater were not unified.•Surface water and groundwater accumulated different kind of dominant antibiotics.•Algae was the most sensitive to the antibiotics compared to the daphnids and fish.
The integration of diagnostic and therapeutic functionalities on a single theranostic nano‐system holds great promise to enhance the accuracy of diagnosis and improve the efficacy of therapy. Herein, ...a multifunctional polymeric nano‐micelle system that contains a photosensitizer chlorin e6 (Ce6) is successfully fabricated, at the same time serving as a chelating agent for Gd3+, together with a near‐infrared (NIR) dye, IR825. With a r1 relativity 7 times higher than that of the commercial agent Magnevist, strong fluorescence offered by Ce6, and high NIR absorbance attributed to IR825, these theranostic micelles can be utilized as a contrast agent for triple modal magnetic resonance (MR), fluorescence, and photoacoustic imaging of tumors in a mouse model. The combined photothermal and photodynamic therapy is then carried out, achieving a synergistic anti‐tumor effect both in vitro and in vivo. Different from single photo treatment modalities which only affect the superficial region of the tumor under mild doses, the combination therapy at the same dose using this agent is able to induce significant damage to both superficial and deep parts of the tumor. Therefore, this work presents a polymer based theranostic platform with great potential in multimodal imaging and combination therapy of cancer.
Multifunctional polymeric nano‐micelles containing a photosensitizer, which at the same time serves as a chelating agent for Gd(III), together with a near‐infrared absorbing dye, are fabricated. Utilizing these theranostic nano‐micelles, combined photothermal and photodynamic therapy, which is guided under triple‐modal magnetic resonance, fluorescence, and photoacoustic imaging, is conducted, achieving a synergistic anti‐tumor effect in a mouse model.
Short circuit faults in an excitation winding pose a potential threat to the safe and stable operation of turbine generators. Some turbine generators are forced to shut down for an overhaul whenever ...a fault occurs, and the economic losses can be serious. In this paper, a 2-D simulation model has been established using the basic electromagnetic and structural parameters of a generator. Here, the generator's excitation current at normal working conditions is calculated, and two binary function is used for the calculation of no-load electromotive force (EMF) expectations on the excitation current and active power is derived. Based on the fundamental characteristics associated with the reduction of effective turns in the excitation winding after a short circuit, the excitation winding short circuit fault can be determined using the deviation between the actual value and the desired value of generator no-load EMF. Fault examples showed that this method can achieve higher diagnosis accuracy, and that it can be used for the real-time monitoring and diagnosis of an overall excitation winding health inside a turbine generator.